A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5895-01-401-5388
NSN 5990-01-145-2878
NSN 5965-00-739-2063
NSN 5935-01-634-0668
NSN 5965-00-518-0958
NSN 5965-00-153-5216
NSN 6610-01-062-9994
NSN 6240-01-390-6354
NSN 6130-01-621-0294
NSN 6220-00-266-8222
NSN 5935-00-997-9437
NSN 5945-00-316-3586